The present invention relates generally to methods of managing network traffic. More particularly, the invention provides methods and systems for rate limiting the flow of control traffic to a CPU. Merely by way of example, the invention has been applied to a rate limiter with a configurable time window, a counter, and a configurable threshold value. But it would be recognized that the invention has a much broader range of applicability.
In communications networks, both data and control packets are processed through the network. At various network devices, control packets, which are related to various control protocols, are received and directed to the CPU resident in the network device. Preferably, control traffic received at the network ports of a network device is identified and directed to the CPU for processing. As an example, control traffic can be trapped or mirrored to the CPU. Trapping of packets involves sending control packets only to the CPU. Mirroring to the CPU involves forwarding control packets to a network egress port, but also sending a copy of the control packets to the CPU.
As the volume of network traffic increases, the number of control packets sent to the CPU increases as well. Thus, there is a need in the art for improved methods and systems for rate limiting control traffic to the CPU for network switching and routing devices.